The best-selling first-person action game of all time gets even bigger with more epic new multiplayer content! The Modern Warfare 2 Resurgence Pack delivers five incredible new multiplayer maps. Take the action to exciting new locations, then battle across legendary landscapes from Call of Duty 4: Modern Warfare.

If you already have Steam installed you can click here to install or play. If you don't have Steam, you can download it here.
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Updates to Left 4 Dead 2 have been released. The updates will be applied automatically when your Steam client is restarted. The major changes include:

Left 4 Dead 2
New mutation: Versus Survival
Updated default configuration for Intel HD Graphics card
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Call of Duty: Black Ops (PC)One fantastic looking game.
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Updates to Team Fortress 2 have been released. The updates will be applied automatically when your Steam client is restarted. The major changes include:

Server Browser
Server browser now starts centered onscreen when it opens up.
Filter panel now starts expanded, instead of hidden.
Added a warning dialog that pops up to warn players joining games with more than the recommended number of players.
Added a "max player count" filter setting.
Renamed quick list checkbox from "Show Map List" to "Simp... [read more]

Updates to Battlefield: Bad Company 2 have been released. The updates will be applied automatically when your Steam client is restarted.

All game servers will need to be taken down for updates. The maintenance period starts on Wednesday Jun 30th at 07:00AM (GMT+2). Most of them should be back up by 11:00AM (GMT+2).

Changelog:

Server - Some potential sources for lag/rubberbanding have been eliminated
Server - The old reserved slots has been replaced by a kick-on-demand system like in BF2
Serve... [read more]

We’ve just released a small Killing Floor update thorugh Steam – everyone who owns the game will find it auto-updating to pick up the changes. If in doubt, just exit Steam and restart it. The issues we have picked up are: Firstly, some general bits and pieces: Fixed clients hanging during map change Fixed an [...]
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This update provides numerous skeletal mesh improvements, improved bloom with added properties, and more. Read the readme for details.
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Medal of Honor (PC)In the Tier 1 interview series you hear personal stories from U.S. Special Operatives who acted as consultants on the development of the game.
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Updates to Counter-Strike: Source have been released. The updates will be applied automatically when your Steam client is restarted. The major changes include:

Counter-Strike: Source
Fixed several problems with missing textures in community maps.
Fixed a crash that could occur when stats get updated.
Fixed a crash that could occur when displaying the scoreboard.
Added "cl_show_achievement_popups", a convar that is on by default. Turning it off disables in-game achievement announcements.
Restric... [read more]

Medal of Honor (PC)A new game, a lot that's familiar.
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